Hormonal contraceptive use in Norway, 2006-2020, by contraceptive type, age and county: A nationwide register-based study - NTNU
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Norsk Epidemiologi 2021; 29 (1-2): 55-62. DOI: 10.5324/nje.v29i1-2.4046 55
Hormonal contraceptive use in Norway, 2006-2020, by
contraceptive type, age and county: A nationwide
register-based study
Kari Furu1,2, Ellen Barth Aares3, Vidar Hjellvik1 and Øystein Karlstad1
1) Department of Chronic diseases and Ageing, Norwegian Institute of Public Health, Oslo, Norway
2) Centre for Fertility and Health, Norwegian Institute of Public Health, Oslo, Norway
3) Norwegian Medicines Agency, Oslo, Norway
E-mail: kari.furu@fhi.no. Telephone: +47 95221824
ABSTRACT
Aim: Our aim was to study hormonal contraceptive use among women in Norway during 2006-2020 according
to age groups and geography, including choice of contraceptive method, type of prescriber for long-acting
reversible contraceptives, and prescriber’s adherence to the national health authority recommendations.
Material and methods: We conducted a nationwide drug utilization study including all women aged 16-49
years in Norway during 2006-2020. The Norwegian Prescription Database (NorPD) includes detailed informa-
tion about all dispensed prescription medications from Norwegian pharmacies to individuals in ambulatory care,
including year of dispensing, patient’s year of birth and county of residence, and the prescriber’s profession.
Results: This study shows a slight increase in overall use of hormonal contraceptives among 16-49-year-olds
during 2006-2018, increasing from 36% of the population to 40%. Combined oral contraceptives (COCs) was
the most commonly used hormonal contraceptive method in all age groups. The use of COCs decreased during
the period and the decline was greatest in those below 25 years. From 2016 80% of all new users of COCs
received the recommended COC containing levonorgestrel. Use of estrogen-free contraceptives, long-acting
reversible contraceptives (LARCs) and gestagen pills, has increased. After 2014 the use of LARCs, especially
subdermal implant, increased steeply among younger women. Oslo had the lowest proportion of users of
hormonal contraceptives among teenagers and young adults during the whole period, while among 30-49-year-
olds Oslo was more in line with the other counties.
Conclusion: Combined oral contraceptives (COC) was the most used hormonal contraceptive method in all age
groups. However, the use of COCs decreased during the period, especially in those < 25 years, where a
corresponding increase in the use of LARC has taken place, mainly from 2014 onwards. Four out of five women
who initiated COC received the recommended COC type and the steep increase in use of estrogen-free LARCs
in recent years implies that Norwegian prescribers have high compliance with the recommendations from the
health authorities.
This is an open access article distributed under the Creative Commons Attribution Licence, which permits unrestricted use, distribution, and reproduction in
any medium, provided the original work is properly cited.
BACKGROUND had a lower risk of VTE than those who use third (e.g.
Marvelon® containing desogestrel) or fourth generation
The first combined oral contraceptives containing both contraceptives (e.g. Yasmin® containing drospirene).
progestagen and estrogen were launched in the 1960s. The review led to an update of the product information
Since then, the estrogen component has decreased due for each of the individual COCs and a decision by
to association with the risk of venous thromboembolism. NoMA to send out a letter to healthcare professionals.
Later on the progestagen component has received more Subsequently, all prescribers in Norway received a
attention as some studies reported different risks of letter with updated information in January 2014 (5). To
venous thromboembolism (VTE) by type of gestagen reduce the risk of VTE NoMA recommends that women
(1,2). In 2009, the Norwegian Medicines Agency who begin with hormonal contraception choose one of
(NoMA) recommended that new users of combined oral these options: long-acting reversible contraceptive
contraceptives should be prescribed those containing (LARC), gestagen pill, or combined oral contraceptive
the progestagen levonorgestrel (called “second- (COC) with estrogen and levonorgestrel.
generation contraceptives”). In 2010, NoMA launched To prevent unwanted pregnancies and abortions among
a campaign in collaboration with the Norwegian teenagers the Norwegian Ministry of Health introduced
Directorate of Health to make the change in national a reimbursement scheme with free contraceptive pills
recommendations known (3). Later, in November 2013, for girls aged 16 to 19 from 1 January 2002. In addition,
the European Medicines Agency (EMA) completed its public health nurses and midwives in public school
review of combined hormonal contraceptives, parti- health services were permitted to prescribe oral contra-
cularly of the risk of VTE associated with their use (4). ceptives to girls in the same age group from 1 June 2002
The conclusion was that women using second- (6,7). This arrangement has been changed several times
generation contraceptives (containing levonorgestrel) (Info Box 1) and as of 2016 public health nurses have56 K. FURU ET AL.
Info Box 1. An overview of changes in reimbursement scheme for hormonal contraceptives and changes in public health nurses'
and midwives' rights to prescribe contraceptives in Norway during 2002-2020.
Reimbursement scheme Prescribing regulations
2002 January: Free of charge for selected contraceptive pills (Trionetta®, June: Public health nurses and midwives
Trinordiol®, Follimin®, Loette® and Microgynon®) for women aged 16 were given the right to prescribe
to 19 years selected contraceptive pills (Trionetta®,
Trinordiol®, Follimin®, Loette® and
Microgynon®) for women aged 16 to 19
years
2006 March 2006: a fixed reimbursement rate introduced for hormonal Public health nurses and midwives’
contraceptives for women aged 16-19*. The reimbursement was set to rights to prescribe were extended to
cover up to NOK 100 for 3 months of use. This reimbursement scheme cover several contraceptive
was to replace the scheme with free contraceptive pills and be extended preparations, including contraceptive
to include more contraceptive preparations such as contraceptive patches, rings and contraceptive patches
contraceptive ring and contraceptive injection (the scheme covers the
gestagen pill Cerazette® and all preparations except for subdermal
contraceptive implant (p-stav) and hormonal intrauterine device (spiral)
2015 The subdermal contraceptive implant and hormonal intrauterine device
were included in the reimbursement scheme
2016 Public health nurses and midwives were
given the right to prescribe all hormonal
contraceptives including long-acting,
reversible contraceptives (LARC) for
women 16 years and older
2018 The reimbursement scheme to include all contraceptives in the ATC
groups G02B, G03AA, G03AB, G03AC and copper IUD. The scheme
has been extended to apply to women from 16 to 20 years of age*
2019 The scheme has been extended to apply to women from 16 to 21 years of
age* (the scheme applies from the month after the woman turns 16 up to
and including the month before the woman turns 22)
* Some contraceptives will be completely free while others (some LARC) will have a co-payment (egenandel), for this age group. Per 2019:
Young women between the ages of 16 and 22 receive contraceptives free of charge or have part of the costs covered. Women who are 16, 17,
18 or 19 years old receive an intrauterine device and a subdermal implant free of charge. Women who are 20 or 21 years, do not get the full cost
covered and must pay a deductible (egenandel).
had the right to prescribe all contraceptives including contraceptives (LARCs)). We grouped the hormonal
LARCs to women 16 years and older (8,9). contraceptives into four groups (Table 1). All women
Our aim was to study hormonal contraceptive use aged 16-49 years during 2006-2020 were included.
among women in Norway during 2006-2020 according We computed three-year prevalence of LARCs (group
to age groups and geography, including choice of 3) and one-year prevalence of the other groups of
contraceptive method, type of prescriber for long-acting contraceptives. The three-year prevalence of LARCs in
reversible contraceptives, and prescriber’s adherence to 2006 for age group 16-49 was computed as the number
the national health authority recommendations. of women born in the period 1957 through 1990 who
were dispensed at least one LARC in 2006, 2005, or
MATERIAL AND METHOD 2004, divided by the population of 16-49-year-old
women per 1.1.2006 from Statistics Norway. Corre-
The nationwide Norwegian Prescription Database spondingly, for other years, groups of contraceptives
(NorPD) includes detailed information about all pre- and age groups. The three-year prevalence for LARCs
scription medications dispensed from Norwegian phar- prescribed by doctors was computed the same way but
macies to individuals in ambulatory care (10), including ignoring all prescriptions where the prescriber was not
year of dispensing, patient’s year of birth and county of a doctor (ForskriverProfesjonKode = LE). Similarly,
residence, and prescriber’s profession. All medications for nurses/midwives (ForskriverProfesjonKode = SP or
in NorPD are classified according to the Anatomical JO).
Therapeutic Chemical classification (ATC) system (11). The numerator for the prevalence of any contra-
There are several types of hormonal contraceptives on ceptives combined in 2006 was the number of women
the market in Norway: some contraceptives containing who received a LARC in 2004-2006 or a contraceptive
both progestagen and estrogen (COCs, vaginal rings, in group 1, 2, or 4 in 2006. We had access to individual
patches), and some containing only progestagen level data for 2004-2018 (Ethical approval: 2017/2546/
(gestagen pills and different long-acting reversible REK sør-øst) but had used tabulated data from a web-HORMONAL CONTRACEPTIVE USE IN NORWAY 2006-2020 57
Table 1. Subdivision of different hormonal contraceptives into 4 groups.
Group Contraception type ATC codes Hormone content Norwegian designation
1 Combined oral contra- G03AA06, G03AA07, Estrogen & progestagen Kombinasjons p-piller
ceptive pills (COC) G03AA09, G03AA12,
G03AA14, G03AB03,
G03AB04, G03AB08
2 Gestagen pills G03AC01, G03AC02, Progestagen Gestagenpiller/minipiller
G03AC03, G03AC09
3 Long-acting reversible G03AC08 Subdermal Progestagen p-stav
contraceptives (LARC) contraceptive implant;
G02BA03 Intrauterine livmorinnlegg/hormonspiral
device (IUD)
4 Other contraceptives G02BB01 Vaginal ring; Estrogen & progestagen Vaginal ring
G03AA13 p-patch; Estrogen & progestagen p-plaster
G03AC06 p-injectable; Progestagen p-sprøyte
G03HB01 antiandrogen Estrogen & antiandrogen p-pille med antiandrogen
based application (similar to the public webpage and from 7.8% to 26% for 20-24-year-old women. Use
http://norpd.no/Prevalens.aspx, but a bit more detailed) of progestagen pills increased gradually, but more for
for 2019-2020. The combined one- and three-year pre- the youngest age-groups: from 3.4% in 2006 to 11% in
valence was not possible to obtain from this application, 2020 for 16-19-year-olds and from 6.4% to 12% for 20-
and thus the combined prevalence is lacking for 2019 24-year-old women. Use of other contraceptives, e.g. p-
and 2020. patches and vaginal rings, has decreased throughout the
For prevalence per county, the 2020 definition of period.
counties was used. Patients who were dispensed medi- Among women who started with COC as their first
cations as residents of two (or more) counties the same ever hormonal contraceptive between 2007 and 2010,
year were counted as users in both (all) counties. For 40% of users were prescribed the recommended
three-year prevalence in e.g. 2009, patients who lived in levonorgestrel-containing COC. From 2011 the propor-
county X in 2007 or 2008 were counted as users in tion of COC-starters who filled a prescription of the
county X in 2009 independent of where they lived in recommended COC increased, and after 2016 the pro-
2009 (we did not have access to individual domestic portion was over 80% (table 2). The highest proportion
relocation history). of new users of the recommended COC was among 17-
Among women who started with a COC as their first 18-year-old girls in 2017-2018; about 87-89%.
ever hormonal contraceptive, we computed the propor-
tion who started with a recommended levonorgestrel-
containing COC (ATC code G03AA07 or G03AB03)
by year and age. Table 2. Number (N) of new users of combined oral
contraceptives (COC) in the period 2006-2018, and the
proportion (%) of these that filled a prescription of a
RESULTS levonorgestrel-containing COC (ATC code G03AA07 or
G03AB03). New use is defined as having no COC
The use of hormonal contraceptives was assessed in 2.3 prescription in NorPD before the year of interest, but pre-
million women in Norway aged 16-49 years. There was scriptions for other hormonal contraceptives are allowed.
a slight increase in overall use of hormonal contra- 16-49 years
ceptives among 16-49-year-olds during 2006-2018,
Proportion (%) prescribed
ranging from 36% to 40%. Among 16-19-year-old Year of Number (N) of new a levonorgestrel-
women, the prevalence of overall use varied from 53% dispensing users of COC containing COC
in 2012-2014 up to 57% in 2018. The proportion of 2006 47085 58.8
users was highest among 20-24-year-old women, in- 2007 41604 38.0
creasing from 63% in 2006 to 69% in 2018 (figure 1). 2008 37928 41.6
2009 34957 36.4
Combined oral contraceptives (COC) was the most
2010 34656 38.0
frequently used method in all age groups. However, the
2011 33311 44.4
use of COCs decreased during the period and the 2012 32437 63.5
decline was greatest in those below 25 years: from 49% 2013 32823 68.7
in 2006 to 30% in 2020 in 16-19-year-old and from 48% 2014 32021 76.0
to 38% in 20-24-year-old women. The use of LARCs 2015 30292 78.1
was quite stable until 2014. After 2014 the use of 2016 28647 80.1
LARCs increased especially among younger women: 2017 26748 81.6
from 5.7% in 2015 to 25% in 2020 for 16-19-year-old 2018 24826 80.758 K. FURU ET AL.
Figure 1. Prevalence (%) of women in different age-groups who filled prescriptions of various types of hormonal
contraceptives in the period 2006-2020. Three-year prevalence for LARC, one-year prevalence for the other groups.
Labels: COC= Combined oral contraceptives with estrogen and progestagen; LARC= Long-acting reversible contra-
ceptives (Subdermal implant & Intrauterine device with progestagen); Other: vaginal ring, p-patch, p-injectable, COC
with estrogen and antiandrogen.
Figure 2. Three-year prevalence (%) of women who have filled prescriptions for Long-acting reversible contra-
ceptives (LARC): intrauterine device with progestagen (ATC code G02BA03) or implant (ATC code G03AC08) by
age group in the period 2006-2020.
The use of LARCs was quite stable among women In 2015, 3.3% of new users of LARCs among 16-19-
over 30 years but increased in teenagers and young year-old girls were prescribed LARC by a public health
adults during the observational period (figure 2). Use of nurse, increasing to 58.3% in 2020. Similarly, for 20-
implant increased steeply from 5.1% in 2015 to 21.2% 24-year-old women 0.4% got their first prescription of
in 2020 for women aged 16-19 years and similarly from LARC from a public health nurse in 2015, increasing to
5.5% to 17.3% for women aged 20-24 years. Use of 21.8% in 2020 (Table 3).
intrauterine devices (IUDs) was lowest among teenagers Oslo had the lowest proportion of users of hormonal
and highest among those >30 years. However, after contraceptives among teenagers and young adults during
2015 the increase in use of IUDs was greatest in the the whole period, while among those 30-49 years, Oslo
youngest: from 0.7% in 2015 to 5.6% in 2020 for 16-19 was more in line with the other counties (figure 3).
years and from 2.4% to 10.0% for women aged 20-24 Innlandet county had the highest proportion of users in
years. those below 30 years. Among women 30-49-year-old,HORMONAL CONTRACEPTIVE USE IN NORWAY 2006-2020 59
Figure 3. Prevalence (%) of use* of any hormonal contraceptive in women by county and age group in the period 2009-2018.
Two-year averages and sorted by increasing prevalence in the 20-24 age group. *A filled prescription for LARC at least once
the actual year or the two years before (“three-year prevalence”), or a filled prescription for other contraceptives the actual year.
Table 3. Number (N) of new users of LARC in the period 2013- 2018, and the proportion (%) of these that filled
their first prescription of LARC from a public health nurse or a midwife. New use is defined as having no LARC
prescription in NorPD before the actual year, but prescriptions of other hormonal contraceptives are allowed.
16-19 years 20-24 years
Number of Proportion Number of Proportion
Year of new users of prescribed by new users of prescribed by
dispensing LARC (N) nurse/midwife (%) LARC (N) nurse/midwife (%)
2013 1445 1.2 3131 0.2
2014 1889 1.5 3754 0.1
2015 5061 3.3 4831 0.4
2016 9223 45.1 6736 14.4
2017 11295 53.1 7881 17.6
2018 12658 58.3 8609 21.8
the proportion of users in 2017-2018 varied from 24% users was highest among 20-24-year-old women (69%
in Nordland county to 30% in Trøndelag county. Among in 2018). Combined oral contraceptives (COC) was the
women 16-19 years, the proportion of users in 2017- most commonly used hormonal contraceptive method
2018 varied from 37% in Oslo to 65% in Innlandet. in all age groups. However, the use of COCs decreased
Among women 20-24 years, the proportion of users in during the period, especially in those below 25 years,
2017-2018 varied from 60% in Oslo to 80% in where a corresponding increase in the use of LARC has
Innlandet. taken place, mainly from 2014 onwards. The inclusion
of implants and IUDs in the reimbursement scheme in
DISCUSSION 2015, and the authorization of public health nurses and
midwives from 2016 to prescribe all hormonal contra-
This nationwide study shows a slight increase in overall ceptives including LARCs for women 16 years and
use of hormonal contraceptives among 16-49-year-olds older may explain this increase. Especially for women
during 2006-2018, from 36% to 40%. The proportion of aged 16-19 years, public health nurses and midwives60 K. FURU ET AL. prescribed LARCs to more women than doctors from younger women. In an ecological study Hognert et al 2017 and onwards. 80% of all women who started with found that the increase of LARC use consisted mainly COC received the recommended type of COC from of a higher use of IUD rather than implant in Sweden 2016 onwards. Use of estrogen-free contraceptives, i.e. and Denmark (19). LARCs and gestagen pills, has increased during the A recently published article reports two women in study period. The steep increase in use of LARCs after Norway with ulnar nerve injuries after removal of 2014 among younger women was mainly driven by an subdermal contraceptive implants (20). The implant is increased use of subdermal implants. The use of placed in the medial upper arm and may lie close to gestagen pills has also increased in younger women important neuromuscular structures. In both cases, nerve over the period, but less and more evenly than the use injury occurred during removal of the implant. The of LARCs. Oslo had the lowest proportion of users of authors of the case report recommend that any patient hormonal contraceptives among teenagers and young with an implant that is not readily palpable in the sub- adults during the whole period, while among those 30- cutaneous tissue should be referred to a hand surgeon 49 years Oslo was more in line with the other counties. who has training in exploring peripheral nerves. Both the Norwegian and European Medicines Agen- The need for contraception may vary between women cy have recommended new users of COC to use the 2nd with different cultural backgrounds, and a study in generation COC containing levonorgestrel. In addition, Norway by Omland et al found lower use of hormonal they have recommended that more women should be contraceptives among immigrants than among women prescribed LARCs to prevent unwanted pregnancies born in Norway without immigrant background. The and abortions, especially among younger women. The differences were greatest between the youngest women fact that since 2016 four out of five new users obtained (21). Oslo has the highest proportion of people with the recommended COCs and the steep increase in use immigrant background in the age-group 16-19 years of LARCs in later years implies high compliance with (38% in 2020), Viken the second highest (18%) and these recommendations in Norway. Public health nurses Nordland county the lowest proportion (9%) of people and midwives contribute to a great extent to this in- with immigrant background (22). These differences crease. Ekman and Skjeldestad have shown that public may partly explain why Oslo has the lowest proportion health nurses and midwives had the highest compliance of users of hormonal contraceptives among teenagers with the prescribing recommendations (12). In their and young adults. annual report of adverse events in 2017, NoMA stated they had not received any reports of deaths due to pul- Strengths and limitations monary embolism in users of COCs for the past seven The NorPD is a well-recognised high-quality data source years. They also reported a marked decrease in the for examining medication utilisation patterns. However, number of admissions for deep vein thrombosis among NorPD lacks information on use of non‐hormonal forms young women in general in the period 2011-2016 accor- of contraception as copper IUDs and condoms. Further, ding to data from the Norwegian Patient Register (13). LARCs supplied directly from health clinics, doctors’ LARCs provide an increased protection against un- own practices or by hospitals may not be captured wanted pregnancies since implants and intrauterine within NorPD. This may lead to an underestimation of devices have few or no user errors. In recent years, total LARC use in our study. However, in 2017, 7000 LARCs have increasingly been recommended in most prescriptions of hormonal contraceptives were provided countries as a strategy to reduce unintended pregnancies from pharmacies directly to doctors’ own practices or and abortion rates (14-17). We demonstrate an increase health clinics, and are registered as aggregated data (not in dispensing of LARCs from 2015 especially among linked to the individual woman that received the contra- the younger women. The decline in abortions in ceptives) in the Norwegian Prescription Database (23). Norway has been highest among women younger than These 7000 prescriptions only accounted for 0.06% of 25 years where there has been the largest increase in the all dispensed contraceptives in 2017 (24). Another limi- use of LARCs (18). The age group 20-24 years has long tation is that we have not excluded pregnant women in had the highest incidence of abortions but has since our analyses, which may also lead to an underestimation 2016 been lower than the abortion rate in the age groups of hormonal contraceptive use among women in 25-29 years and 30-34 years. An important contribution Norway. to the increase in use of LARCs may be both the exten- It is reasonable to assume that the NorPD reflects real sions of providing all types of hormonal contraception use of medications. However, filled prescriptions do not free of charge to younger women from 1 January 2015 necessarily mean that the contraceptives have been and giving the public health nurses right to also used, and no data on discontinuation were available. prescribe LARCs from 2016. This increase is in LARCs tend to give some intolerable side effects, most accordance with the recommendations from the health importantly bleeding disorders, albeit transient, and authorities. Smaller IUDs were introduced to the these are frequently reasons for discontinuation. Never- Norwegian market in 2014 and 2017 (Jaydess® and theless, when assessing contraceptive use, dispensed Kyleena®) and these are more acceptable for women contraceptives from pharmacy have been shown to be who haven’t given birth to a child. This may also have more reliable than self-reported use, as women tend to contributed to the increased use of IUDs among overestimate their contraceptive use (25).
HORMONAL CONTRACEPTIVE USE IN NORWAY 2006-2020 61
In summary, our results show a marked increase in Funding
the use of the preferred hormonal contraceptives The study was partly supported by NordForsk Nordic
(LARC, gestagen pill, COC with levonorgestrel) that Program on Health and Welfare (Nordic Pregnancy Drug
reduce the risk of VTE. The prescribing doctors, public Safety Studies, project No. 83539), by the Research Council
health nurses and midwives in Norway have high of Norway (International Pregnancy Drug Safety Studies,
project No. 273366) and by the Research Council of Norway
compliance with the recommendations from the health through its Centres of Excellence funding scheme (project No.
authorities. 262700).
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